1. Technical Field
The present invention relates to a light emitting device and a projector.
2. Related Art
A super luminescent diode (hereinafter, referred to as “SLD”) is a semiconductor light emitting device that can output several hundreds of milliwatts like a semiconductor laser, while exhibiting a broadband spectrum and thus being incoherent like a typical light emitting diode.
The SLD can be used as a light source of a projector, for example. In order to realize a light source having high power and small etendue, it is desirable that lights output from plural gain regions travel in the same direction. In Patent Document 1 (JP-A-2010-192603), by combining a gain region having a linear shape and a gain region having an arc shape, lights output from light emitting area of the two gain regions are allowed to travel in the same direction.
To reduce loss of an optical system and reduce the number of optical component, a type of a projector that can perform light collimation and uniform illumination simultaneously by providing an SLD immediately below a light valve and using a lens array, has been proposed. In the projector of that type, it is necessary to provide light emitting area according to the lens array.
In the SLD described in Patent Document 1, it is difficult to arrange plural light emitting area at large distances according to the lens array, and the SLD is not applicable to the projector of the above described type.